Related Experiment Video
Updated: Apr 3, 2026

Quadruple-Checkerboard: A Modification of the Three-Dimensional Checkerboard for Studying Drug Combinations
Published on: July 24, 2021
Probable interaction between acenocoumarol and levofloxacin: a case series
I Palacios-Zabalza1, M Bustos-Martínez1, J Peral-Aguirregoitia1
1Department of Pharmacy, Galdakao- Usansolo Hospital, Galdakao, Bizkaia, Spain.
Concomitant use of acenocoumarol and levofloxacin may cause dangerous fluctuations in blood clotting. Closer patient monitoring is crucial, particularly for the elderly and those with kidney issues.
Area of Science:
- Pharmacology
- Drug Interactions
- Clinical Medicine
Background:
- Acenocoumarol is an anticoagulant used for long-term management of thromboembolic disorders.
- Levofloxacin is a broad-spectrum antibiotic commonly prescribed for various bacterial infections.
Observation:
- Five patients on stable acenocoumarol therapy experienced sudden, unexplained changes in their international normalized ratios (INRs).
- These erratic INR changes occurred after initiating treatment with levofloxacin, with no other identifiable cause.
Findings:
- A probable drug interaction between acenocoumarol and levofloxacin was identified.
- The interaction led to significant and unpredictable alterations in anticoagulation levels.
Implications:
- Concomitant use of acenocoumarol and levofloxacin necessitates closer INR monitoring.
- Elderly patients and those with renal dysfunction may be at higher risk for severe interactions.
More Related Videos
07:51High-throughput Identification of Synergistic Drug Combinations by the Overlap2 Method
Published on: May 21, 2018
09:24Application and Methodology of the Non-destructive 19F Time-domain NMR Technique to Measure the Content in Fluorine-containing Drug Products
Published on: August 22, 2017
Related Concept Videos
Pharmacokinetics: Drug–Drug Interactions
Drug toxicity: Drug–Drug Interaction
Pharmacokinetics: Drug–Food and Drug–Viral Interactions
Factors Affecting Protein-Drug Binding: Drug Interactions
Displacement interactions can have varying outcomes, ranging from toxicity to virtually...
Combined Effects of Drugs: Antagonism
The most common type is receptor antagonism, where one drug acts as an antagonist to block the effects of another drug by...
Combined Effects of Drugs: Synergism
Such synergistic combinations...